1. Field of the Invention
The present invention relates to an abnormality determination apparatus for determining an abnormality in an angle detection device configured to output a signal having a value varying periodically in synchronization with rotation of a rotating body.
2. Description of Related Art
Japanese Patent No. 3938902 discloses such an angle detection apparatus configured to detect its output gain based on the value of the output signal thereof divided by the value of a sine function or a cosine function whose phase is a current rotational angle of a rotating body.
However, if there is an abnormality in the angle detection device, and accordingly, the angle detection device cannot correctly detect its output gain, it is not possible to obtain correct information showing the current rotational angle of the rotating body.